Satellite servicing

ABSTRACT

This invention relates to an improved satellite servicing system. The improvements include improvements in payload distribution in the cargo bay of the Shuttle Orbiter and improvements in the location of the targets required for positioning end effectors with respect to the component which they are to engage. In the improved satellite servicing system, the remote manipulator system which is normally used for the purpose of capturing and deploying satellites is also used for servicing the satellites when captured and secured for servicing. An improved payload distribution system is provided in the cargo bay which permits optimum utilization of the cargo bay by primary payload units by providing for the location of secondary payload units at any convenient position of opportunity along the length of the cargo bay. In the improved target system, targets are mounted at a site which is remote from the complementary component which is to be engaged by the end effector carried by the manipulator arm such that the target does not permanently obscure the line of vision of the television camera which is mounted on the remote manipulator.

This is a continuation of application Ser. No. 54,829, filed July 3,1979 now U.S. Pat. No. 4,273,305 issued June 16, 1981.

This invention relates to The Space Shuttle Orbiter. In particular, thisinvention relates to an improved satellite servicing system andimprovements in the payload distribution in the cargo bay of a SpaceShuttle Orbiter.

A satellite servicing system is described in U.S. Pat. No. 4,079,904,dated Mar. 21, 1978. In this known system, the remote manipulator armwhich is used for the purposes of capturing and deploying an orbitingsatellite is not used for the purposes of exchanging modules between thesatellite and the replacement module assembly. The module exchangemechanism of this prior patent is capable of operating independently ofthe remote manipulator arm. This mechanism has previously been used inconjunction with a relatively large replacement module storage magazine.The module exchange mechanism and replacement module storage magazineare generally housed in the aft section of the cargo bay so that theforward section is available for using in stowing a primary payloadassembly such as a satellite, an orbiter probe or the like. Thereplacement module storage magazine and the module exchange mechanismpreviously proposed occupied a substantial portion of the cargo bay andthus effectively reduced the payload capacity of the cargo bay. Toprovide for the most efficient use of the orbiter, it is important tomaximize the payload capacity of the cargo bay and to minimize theportion of the cargo bay utilized for the stowing of secondary payloaditems such as replacement modules and the Module Exchange mechanism foreffecting transfer of replacement modules between the replacement modulestorage device and the satellite which is to be serviced.

It is an object of the present invention to provide an improvedsatellite servicing system for an orbiter in which the RemoteManipulator System which is normally used for the purpose of capturingand deploying satellites is also used in the servicing of satelliteswhen captured and secured for servicing.

A further object of the present invention is to provide an improvedpayload distribution system in a cargo bay of an orbiter which permitsthe optimum utilization of the cargo bay by primary payload units byproviding for the location of secondary payload units at a convenientposition of opportunity along the length of the cargo bay.

A further object of the present invention is to provide an improvedtarget system for use in a remote manipulator system wherein the targetis mounted at a site which is remote from the complementary componentwhich is engaged by the end effector such that the target does notpermanently obscure the line of vision of the television camera when thecomplementary component is removed from its support structure.

SUMMARY OF INVENTION

According to one aspect of the present invention there is provided in aspace orbiter having a cargo bay formed therein which has a longitudinalextent in a first direction, said orbiter being adapted to open toprovide access to the cargo bay through an access passage extendingalong said cargo bay in said first direction, an improved satelliteservicing system comprising a remote manipulator system which includes aremote manipulator arm having a first end secured to the orbiter and afree end which may be moved in response to manipulation of the arm to bepositioned at any required point with a predetermined operational rangeextending within and without said cargo bay for use in the capturing,deploying and servicing of satellites and the like, a combined satelliteservice and replacement module support assembly mounted in said cargobay within said operational range of said arm, said support assemblycomprising a support frame mounted in and extending transversely of saidcargo bay within said operational range of said arm, a plurality ofreplacement modules releasably mounted on said support frame in aside-by-side generally planar array, said replacement modules beingaccessible to and releasable by the free end of said manipulator arm, asatellite servicing platform on said frame, said platform being adaptedto support a satellite in a satellite servicing position within saidoperational range of said manipulator arm whereby the manipulatorassembly may be operated to effect an interchange of modules between asatellite located on said platform and modules located on said supportassembly.

According to a further aspect of the present invention, there isprovided a space orbiter having a cargo bay formed therein which has alongitudinal extent in a first direction, an improved payloaddistribution system comprising a remote manipulator assembly operable toperform manipulating functions within a predetermined range along thelongitudinal extent of the cargo bay, mounting means in said cargo bayand located within at least said operational range of said remotemanipulator assembly adapted to operably locate payload assemblies at aplurality of positions along the length of said cargo bay, a firstprimary payload assembly located in said cargo bay and mounted on saidmounting means at a convenient location along the length of said cargobay to provide a free length of cargo bay at a position of opportunityalong the length of said cargo bay, a secondary payload assemblydisposed in said free length of said cargo bay and mounted on saidmounting means, thereby to permit optimum utilization of said cargo bay.

According to a further aspect of the present invention, there isprovided in a remote manipulator system in which a television camera ismounted at the free end of a manipulator arm to relay a target image toa monitor having image alignment markings thereon, the manipulator armhaving an end effector located at the free end thereof for use inmounting and releasing a complementary component with respect to asupport structure, the improvement of a target mounted at a site remotefrom said complementary component on the direct line of vision of saidcamera when said end effector is axially aligned with said complementarycomponent and said complementary component is mounted on said supportstructure, said target being proportioned such that its image viewed atthe monitor is coextensive with the image alignment markings of saidmonitor when said end effector is operably positioned to mount orrelease said complementary component with respect to its associatedsupport structure.

PREFERRED EMBODIMENT

The invention will be more clearly understood after reference to thefollowing detailed specification read in conjunction with the drawings,wherein,

FIG. 1 is a pictorial view of a space orbiter in which the cargo bay isopen to illustrate the location of a combined satellite service andreplacement module support assembly and a plurality of alternatepositions thereof;

FIG. 2 is a pictorial view of the combined satellite service andreplacement module support assembly of FIG. 1 in enlarged detail;

FIG. 3 is a front view of the combined satellite service and replacementmodule support assembly with the modules and their associated latchingframes removed;

FIG. 4 is a view similar to FIG. 3 illustrating the assembly of FIG. 3with the module latch frames mounted thereon;

FIG. 5 is a side view of an orbiter illustrating the location of thecombined satellite service and replacement module support assembly in aposition of opportunity in the cargo bay;

FIG. 6 is a side view of an orbiter similar to FIG. 5 illustrating thelocation of the combined satellite service and replacement modulesupport assembly in a further position of opportunity in the cargo bay;

FIG. 7 is a side view of the free end of the manipulator arm showing themanipulator arm end effector and a module interchange end effectormounted thereon with a television camera mounted on the end effector inalignment with a number of potential target mounting sites; and

FIG. 8 is a front view of a television monitor illustrating the targetalignment technique.

With reference to the drawings, reference numeral 10 refers generally toa Space Shuttle Orbiter. The orbiter has a cargo bay generallyidentified by the reference numeral 12 which, in FIG. 1, is shown in theopen position. The cargo bay 12 extends longitudinally of the SpaceShuttle Orbiter and has its forward end disposed adjacent the crewcompartment of the Shuttle Orbiter which is located in the forward endof the Space Shuttle Orbiter. The Space Shuttle Orbiter haslongitudinally extending doors 14 and 16 which are openable to provideaccess to the cargo bay through an access passage extending along thecargo bay in the direction of its longitudinal extent. The doors 16 and14 are powered for movement between the open position illustrated inFIG. 1 and the closed position totally enclosing the cargo bay.

As in previously proposed cargo bay constructions, a plurality oftrunnion fittings 18 are provided at spaced intervals, generallyeighteen inches, along the length of the cargo bay. The support trunnionfittings 18 extend along substantially the full length of the cargo bayand provide payload support means at spaced intervals along the lengthof the cargo bay for supporting payload units therein.

The Space Shuttle Orbiter 10 is provided with a remote manipulatorassembly which includes a remote manipulator arm 20 which has one endmounted by means of a shoulder joint 22 at a predetermined positionalong the length of one wall of the cargo bay. The arm 20 has a remotemanipulator end effector 26 connected to the free end thereof by a wristjoint 24. The remote manipulator end effector 26 has a television camera27 mounted adjacent thereto. The direct line of vision of the camera 27is arranged to extend from the focal point of the camera along an axisparallel to the longitudinal axis of the end effector 26. The endeffector 26 may be in the form of a grappling device similar to thatdescribed in U.S. Pat. No. 4,105,241, Mee et al, dated Aug. 18, 1978.The end effector 26 may be operably secured with respect to a grapplefixture mounted on a satellite or on any one of a number of tools suchas module release end effectors. The manipulator arm 20 is capable ofoperating over a predetermined operational range B extending within thecargo bay and it is capable of operating without the cargo bay for thepurposes of capturing or deploying an orbiting satellite generallyidentified by the reference numeral 28. The overall length A of thecargo bay may be of the order of about sixty feet with the operationalrange B of the manipulator arm operating in conjunction with theassembly 30 being of the order of about forty feet.

A combined satellite service and replacement module support assemblyconstructed in accordance with the embodiment of the present inventionis generally identified by the reference numeral 30. The assembly 30 maybe located at any required position of opportunity along the length ofthe operational range B, by selecting the most convenient trunnionsupport 18 for use in supporting the assembly 30. By reason of the factthat the assembly 30 may be positioned on any one of the trunnionsupports 18, the most convenient trunnion support may be selected toenable the assembly 30 to be located at substantially any requiredlocation along the length of the cargo bay. As a result, it is possibleto plan the distribution of the primary load based upon the total cargobay length A and thereafter to locate the assembly 30 at any convenientposition of opportunity within the operational range B. It will beunderstood that the primary payload units are supported by trunnionframes which are in turn mounted on the most conveniently locatedtrunnion fitting 18 to achieve the required load distribution. Thus, asshown in FIG. 5 of the drawings, the assembly 30 may be located betweenprimary payloads 32 and 34. The configuration illustrated in FIG. 5 is aconfiguration which might conveniently be used in Flight No. 13 of thecurrent shuttle orbiter flight manifest in which the assembly 30 islocated between the primary payload unit 32 which is the SSUS-A andprimary payload unit 34 which is INTESLAT V.

FIG. 6 illustrates a different payload distribution in which theassembly 30 is located in the aft section of the cargo bay and theprimary payload unit 36 is located in the forward section of the cargobay. This diagram illustrates a possible payload distribution for use inFlight No. 23 in which the primary payload unit is a Jupiter OrbiterProbe.

It will be understood that the payload distribution system of thepresent invention is equally applicable to any other space shuttleorbiter flight.

The combined satellite service and replacement module assembly 30 isillustrated in detail in FIGS. 2, 3 and 4 of the drawings to whichreference will now be made.

The assembly 30 consists of a support frame generally identified by thereference numeral 40, a satellite servicing platform generallyidentified by the numeral 42 and a plurality of replacement modules ofwhich two types are identified by the reference numerals 44 and 46,respectively.

The support frame 40 consists of a perimeter member 48 which isproportioned so as to extend in close proximity to the sides of thecargo bay when located therein. The perimeter member 48 has trunnions 50projecting outwardly therefrom which are adapted to engage the trunnionsupport frame 18 to support the assembly 30 in a position extendingtransversely of the longitudinal extent of the cargo bay. Mounting framemembers 52, 54 and 56 extend transversely across the perimeter member 48and are arranged in a spaced parallel relationship one above the other.A plurality of mounting passages 58 are located at spaced intervalsalong the length of each of the mounting frame members 52, 54, 56.Latching frame members 60 and 62 extend between and are secured toadjacent frame mounting members and are selectively positioned to theproportions required for use in supporting the replacement modules 44and 46, respectively, by use of the appropriate mounting passages 58,the latching frame members 60 and 62 being bolted to the mounting framemembers through the mounting passages 58 and corresponding mountingpassages at each end of the latching frame members.

The latching mechanism used for releasably securing the replacementmodules with respect to the assembly 30 may be of any convenientlatching structure. In one form, the latching mechanism may includelatching probe assemblies, latching barrel assemblies and latch operatedmechanisms of the type described in U.S. Pat. No. 4,079,904. Thelatching probes are secured with respect to the latching frame membersand remain attached to the support assembly 40 after the module has beenreleased. The latching barrels are carried by the replacement modulesand the latch operator is an end effector located at the free end of themanipulator arm assembly. In the embodiment illustrated in FIG. 4 of thedrawings, latching probes 66 are mounted on the latch frame members 60and identical latching probe members 68 are mounted on the latchingframe members 62. The latching barrels 70 are secured with respect tothe replacement modules 44 and identical latching barrels 72 are securedwith respect to the replacement module 46. The latch operator mechanismis incorporated in the end effector 74 which, during assent and descentof the Space Shuttle, may be parked on a latching probe 76 of the typepreviously described which is located on a support plate 75 (FIG. 2). Asimilar parking latching probe 78 is mounted on the main frame 48 on theopposite side of the satellite support platform 42. Parking latchingprobe 78 may be used to provide a temporary support for modules whichare removed from the satellite which is being serviced so that themanipulator arm may be freed to move a replacement module from thereplacement module storage assembly direct to the satellite.

The satellite service platform 42 consists of a turntable, generallyidentified by the reference numeral 80 which includes a stationarycomponent 82 which is secured with respect to the transversely extendingsupport frame member 86 and a rotating member 88 which is rotatablydriven by a suitable drive mechanism (not shown). The rotating member 88has three arms 92 projecting outwardly therefrom. One or more of thearms 92 may be hingedly connected by means of hinges 94 to the rotatingmember. The hinges 94 permit the satellite docking platform to assume acompact configuration when not in use such that the overall lengththereof is no greater than the length C. The legs or arms of theturntable assembly may also be jettisonable if required.

Visual alignment targets are provided to permit the crew to operablyposition the end effector 26 or the end effector 26 and an associatedend effector 74 with respect to a complementary component such as thebarrel 70 which is to be manipulated thereby. An example of one targetis the target 100 which is associated with the end effector 74 (FIG. 2).It will be noted that the target mounting site of the target 100 is thesupport frame assembly 40 and not the end effector 74. Thus, the target100 is located in a plane which is spaced rearwardly from the interfacewhich will be formed between the end effector 26 and the end effector 74when operably connected to one another. Similarly, the target 100a ismounted on the support frame 40 in a plane spaced rearwardly from theinterface to be formed between the support probe 78 and a replacementmodule temporarily parked thereon. In a like manner a target 100b ismounted at a site on the support frame 40 so as to be associated witheach latching barrel 70.

As shown in FIG. 7 of the drawings, the television camera 27 has adirect line of vision extending along the axis 110 in a plane parallelto the longitudinal axis 112 of the remote manipulator end effector 26on which the camera is mounted.

A monitor 114 is located in the crew cabin for use by the crew inmonitoring the pictures taken by the camera 27. The monitor 114 hasimage alignment markings 116 applied directly to the viewing screenthereof. The visual alignment targets are arranged and proportioned soas to be aligned with and coextensive with the image alignment markingswhen the remote manipulator system is operably positioned with respectto the complementary component associated with the selected visualalignment target. Image outlines 124 and 126 illustrate the progressiveincrease in size of the target image as the camera advances toward thetarget.

As shown in FIG. 7 of the drawings, the position of the focal point 118of the camera is fixed with respect to the plane 120 which is located atthe interface formed between the remote manipulator end effector 26 andthe module interchange end effector 74 and with respect to the secondplane 122 which is located at the interface of the module interchangeend effector 74 and its complementary component. Thus, the size of thetarget required to fully fill the image alignment markings will vary indirect proportion to the distance at which the target is sighted fromthe focal point of the camera. It follows that it is not necessary tolocate the targets in the plane of the various interfaces provided thetargets are located on the direct line of vision of the camera and areproportioned to provide an image which is coextensive with the imagealignment markings 116 when the required interface connection isestablished in use. This is an important feature because it permits thevisual sight targets to be located at any convenient site remote fromand rearwardly from the component which is to be engaged by themanipulator arm in use. Thus, for example, when the end effector 26 isused to engage the end effector 74 the target 100 is used to achieve therequired positioning of the manipulator arm assembly. The target 100remains with the support structure with the result that when the endeffector 74 is removed from its parking probe, the direct line of visionof the television camera will not be obstructed by the end effector 74and the camera may be used to achieve subsequent positioning of the endeffector 74 with respect to a complementary module exchange latchingbarrel.

In use,it is important to achieve maximum utilization of the cargo bayspace in order to provide a maximum payload capacity for primary payloadunits. This desirable objective is achieved in accordance with thepresent invention by reason of the fact that it is possible to plan thelocation of one or more primary payload units at appropriate positionsin the cargo bay and to locate the secondary payload unit in the form ofa replacement module support assembly at any convenient position ofopportunity provided by the distribution of the primary payload unit.Having selected the appropriate primary payload and secondary payloaddistribution, the primary payload items and secondary payload units arelocated as planned in the cargo bay. The space orbiter may then belaunched and made operational to effect deployment of its cargo. Thespace orbiter may also be manoeuvered to close proximity with anorbiting satellite or the like. The remote manipulator assembly may thenbe activated to extend the manipulator arm so that its end effector withthe aid of suitable visual targets engages a grapple device convenientlylocated on the satellite. The manipulator arm may then be manipulated tolocate the satellite on the satellite servicing platform 42. Thesatellite platform 42 may be rotated so that the modules 44 are directedin the general direction of the crew compartment of the space orbiter soas to be visible through observation windows which permit viewing fromthe crew compartment into the cargo bay. The crew then manoeuvers theremote manipulator system to pick up the module exchange end effector 74using the visual target 100. The manipulator arm with the moduleexchange end effector 74 located thereon is manoeuvered to engage themodule release latch mechanisms to release a module 44 a mounted in thesatellite. The module 44a is then transferred by the manipulator arm tothe parking latch 78. A replacement module 44a is then removed from thereplacement module support assembly and located in the compartment whichwas vacated by the module 44a. Thereafter the module 44a is removed fromthe parking latch 78 and mounted on support frame at the positionvacated by the replacement module. This process may be repeated untilall of the required modules have been interchanged.

As shown in FIG. 2 of the drawings and as previously indicated, one ofthe replacement modules may be in the form of a propulsion module 46. Inorder to support the propulsion module in the position to facilitate themanipulation thereof, a special purpose support frame is required. Thespecial purpose support frame is readily mounted on the previouslydescribed main support frame and serves to locate the replacementmodules in a position in which the latching mechanism are readilyaccessible to the end effector.

It will be noted that the combined satellite service and replacementmodules support assembly of the present invention can be positioned inthe cargo bay with the replacement modules mounted on the base thereofwhich is directed toward the forward end of the cargo bay with theresult that the modules and their supporting latch mechanisms arereadily visible from the cargo bay. This permits the crew operator toobserve the manipulations of the remote manipulator mechanism as iteffects latching, unlatching and transfer of the modules between thesatellite service and replacement modules support assembly and asatellite mounted on the support platform in use.

Various modifications of the structure of the present invention will beapparent to those skilled in the art without departing from the scope ofthe invention. For example, the distribution and proportions in thevarious modules which are mounted on the replacement modules support mayvary as required in use. This may be achieved by adjusting the positionof the mounting frame members or the latching frame members of themodule support assembly.

As previously indicated, the latching mechanism used for releasablysecuring the replacement modules and the end effector used inconjunction therewith may be of any convenient latching structure. Inone such proposal, a threaded latching pin is mounted on the latchingframe members and projects outwardly therefrom. A latching nut isrotatably mounted in the replacement modules for engaging the threadedpin and an extending assembly is provided for extending the overalllength of the nut to the front face of the replacement module. In thisembodiment, the end effector 74 would incorporate a rotatably driventool adapted to engage the extending assemblies of the latching nut soas to rotatably drive the latching nuts to engage or release thethreaded latching pins. These and other modifications will be apparentto those skilled in the art.

What I claim as my invention is:
 1. In a space shuttle orbiter having acargo bay formed therein which has a longitudinal extent in a firstdirection extending from the crew compartment located at one endthereof, an improved payload distribution system comprising:(a) a remotemanipulator arm having a proximal end mounted in said cargo bay adjacentsaid one end thereof, said manipulator arm being operable to performmanipulating functions within a predetermined range along thelongitudinal extent of the cargo bay, (b) a plurality of mounting meanslocated at intervals along said cargo bay within said operational rangeof said remote manipulator arm adapted to operably locate payloadassemblies at a plurality of positions along the length of said cargobay, (c) a first primary payload assembly located in said cargo bay andreleasably mounted on a first of said mounting means within theoperational range of said manipulator arm at a convenient location alongthe length of said cargo bay to provide a free length of cargo bay at aposition of opportunity along the length of said cargo bay, (d) asecondary payload assembly disposed in said free length of said cargobay within the operational range of said manipulator arm and releasablymounted on said mounting means, thereby to permit optimal utilization ofsaid cargo bay, said secondary payload assembly comprising a replacementmodule support assembly which consists of a short generally planarsupport frame having a support face extending transversely of the cargobay, said support face facing said one end of the cargo bay, and aplurality of replacement modules releasably mounted on said support facein a side-by-side generally planar array so as to be accessible to saidmanipulator arm and being adapted to be released by operation of saidmanipulator arm in use.
 2. In a space shuttle orbiter for use intransportating primary and secondary payloads, said orbiter having acargo bay which has a front end and a back end and an unrestrictedlongitudinal extent therebetween, a crew compartment being located atone end of said bay, the improvement of a payload distribution systemcomprising(a) a remote manipulator arm having a proximal end mounted onsaid orbiter and a distal end movable along the length of said baywithin a predetermined operational range, (b) a plurality of mountingmeans located inside cargo bay at intervals along the length thereof,(c) a secondary payload mounted on said mounting means at a positionspaced from the front end of the cargo bay to form a forward storagecompartment and spaced from the back end of said cargo bay to form anaft storage compartment, said secondary payload comprising a shortgenerally planar support frame having a support face extendingtransversely of said cargo bay and facing toward the front end of saidcargo bay and a plurality of replacement modules releasably mounted onsaid support face in a side-by-side generally planar array so as to beaccessible to said manipulator arm, (d) a first primary payload disposedin said forward compartment and releasably mounted on said mountingmeans, (e) a second primary payload disposed in said aft compartment andreleasably mounted on said mounting means.